Best app to take 1 picture of sunset every day for 1 year?

I have an old iPhone 3GS and I'd like to mount it on a tripod in my office and take one picture every day around sunset. Ideally, I could feed in a list of days and times, like:
April 20, 2014 6:00pm
April 21, 2014 6:01pm
etc.

and then have it take just one picture at the defined time. Does anyone know of an app that can do this?